There is a continuing increase in the density of vehicles traveling the world's roadways. This increase raises the probability of vehicles colliding with objects. Simultaneously, a need to improve the safety of vehicle operations, as it currently stands, by reducing the occurrences of vehicles colliding with stationary and moving objects (such as roadside obstacles and other vehicles) is present. Motor vehicle safety devices have continuously improved over the years and have made driving a safer experience. Many of these safety devices, such as seat belts and air bags are designed to protect occupants in the event of a crash. Other devices, such as anti-lock braking systems are intended to assist the driver's performance to prevent a crash. Such systems assume an alert and competent driver, but this is not always the case. A driver may not be fully alert or capable of making appropriate decisions for any number of reasons. For example, these include drowsiness, talking on a cellular phone, changing the radio stations, dealing with unruly children, mental fatigue, age, medical conditions and the like.
Driving is a complex task and requires a range of cognitive and psychomotor abilities that include memory, judgment, motor control and speed, decision-making, and attention. These skills are necessary for safe driving and often decline as we age. Aging presses the issue of driving competence. Driving places demands on attention, memory, problem solving and information processing, the cognitive faculties that decline with aging. Older drivers crash at a rate second only to the youngest drivers. Older driver involvement in fatal crashes is projected to increase 155% by 2030, accounting for 54% of the total projected increase in fatal crashes among all drivers. As the population ages and the number of older drivers increases, declining driver competence becomes an urgent public health problem and a challenge to recognize impaired driving ability in the elderly.
Crashes receiving national attention include older drivers reportedly confusing the gas and brake pedals. In all reported cases, the drivers admitted mistakenly using the accelerator instead of the brake. During such unintended acceleration (UA), drivers experience full, unexpected acceleration, often colliding with nearby objects and resulting in injuries or death to the driver or others in the immediate environment. Examination of the vehicles immediately after the accident reveals normally functioning brake and fuel delivery systems.
The cause of UA is not well understood, and measures to predict the likelihood of future UA events do not exist. UA accidents are more likely to involve older drivers (100-600% over-involvement of drivers 60 and older) (U.S. DOT, 1989) and may belie underlying cognitive deficits. The prevalence of cognitive impairment is estimated to be 10% of apparently healthy individuals over the age of 65 in an academic practice (Sager, 2003). While up to one-third of all people aged over 65 years may be demented, even dementia is overlooked in 25 to 90% of older adults, some 5 million people. Age is the primary risk factor for cognitive impairment, dementia, and UA. Thus, cognitive impairment may be a good predictor of UA and UA accidents. Furthermore, specific types of cognitive impairment are likely to be predictive of UA outcomes, and UA may be one outcome of an overall driver pedal error issue.
One means for reconciling these factors is to evaluate a driver's operational performance over time to determine if the driver has lost the capability of operating the vehicle safely. Whenever a driver is responsible for operating a motor vehicle, it is critical that the driver be capable of demonstrating basic cognitive and motor skills at a level that will assure the safe operation of the vehicle. A number of conditions can impair a driver's ability to perform the basic cognitive and motor skills that are necessary for the safe operation of a motor vehicle. It is desirable to evaluate a driver's ability to identify hazardous conditions and correctly react to those conditions while operating a motor vehicle.
Typically, people whose driving capabilities are questioned are evaluated by the Department of Motor Vehicles or an occupational therapist. This requires a human evaluator to ride with the subject and evaluate them based on some criteria. However, road test courses and evaluator training have not been standardized. An evaluator's background and training are variable. This introduces subjectivity and potential bias in that not all road tests are standardized and one cannot control variables such that all subjects will experience the same test or such that all will face specific events that could be a hazard to them. For example, not all drivers would be faced with a pedestrian walking into the path of the vehicle or a car running red light when the driver approaches the intersection with a green light. Further, road tests have relied on the expert opinion of the examiners in which errors are determined either as driving errors that violate the rules of the road or by the judgment of the examiner as to what constitutes an important error. However, some errors are typical of experience drivers (e.g., rolling stop at a stop sign) and may not be relevant to competence decisions. Finally, road tests can be costly and dangerous when the driver is very incompetent.
Laboratory measures, such as neuropsychological tests, have been used to infer poor driving skills based upon poor test performance, but have met with mixed success. While poorer global cognitive performance is associated with impaired driving, the specificity of the neuropsychological measures has been limited. Measures of visual attention and executive function appear to be the most promising of the in-clinic measures. Accident history (often based upon accidents per million miles) has been used to examine whether certain populations are at greater risk for on-road accidents. While this provides a valid measure of “real world” risk, it does not inform individual risks and may over- or underestimate risk depending upon the driving environs.
The emergence of driving simulators have provided an opportunity to evaluate under addressed skills such as accident avoidance and navigational abilities, and to experimentally delineate the components of driving performance. Concerns remain regarding their realism and usability in various populations. Fully interactive driving simulator system are also available that puts drivers behind the wheel before they drive on the highway. These simulators provide 3-screens with an expanded field of view for realism. Alternatively, single-screen system are also available that allow drivers to replicate the actions necessary to develop and reinforce driving skills and habits. These typically include a car seat, steering wheel, accelerator, brake pedals, desktop, console, or customized driving controls; regular, wide field-of-view and head-mounted display options; and validated high-fidelity, non-linear, vehicle and tire models. While there are simulators capable of automatically recording crashes, reaction time, speed, tickets and response to tasks of divided attention, these simulators merely score, but do not determine whether the driver has passed or failed the test. Further, these simulators require a human evaluator to render an opinion as in the road testing.
The creation of the restricted driver classification is important for public health and safety. Many older driver evaluation services are designed to determine who is no longer safe to drive, providing documentation and legitimacy for driving cessation whether forced or voluntary. By acknowledging an intermediate level of driving skill and ability, we are piloting clinic-based driving optimization efforts. The negative consequences of driving cessation are real and deeply felt by many older drivers. Handing over the keys is often tantamount to a resignation of freedom, independent mobility, and management of personal affairs. The psychosocial repercussions of driving cessation demand special consideration. Driving is an important part of mobility and socialization for older adults. Driving cessation is a major decision, often associated with an increase in depressive symptomology and potential social isolation. Access to friends and family, employment, shopping and commerce, personal care, educational and cultural enrichment, and religious expression, often necessitates transportation from one location to another. High levels of mobility mean high levels of access, choice, and opportunity, which can lead to self-fulfillment and enrichment. Low levels of mobility can lead to isolation and cultural impoverishment. Clinical and policy-related discernment of driving fitness must therefore, be carefully executed and guided by proper testing and screening methods. As the numbers of older drivers increase, it becomes essential to optimize driving for capable older adults and to ensure that only those who pose no risk to themselves or others on the road continue to drive.
It would be desirable to have a system that combines a simulator with a method to automatically evaluate a person's driving capabilities and render an outcome of pass, fail, or driving with restrictions without the need for a trained observer to evaluate driver's performance. It would also be desirable to have a system that combines a simulator with a method to automatically assign type of restrictions on drivers with restrictions.
Accordingly, the present invention is directed to these, as well as other, important ends.